Whiskers are single crystals that have a high length to width ratio. When incorporated into the matrix of materials such as ceramics, the result can be a composite having improved strength and toughness. A great deal of research is being done in this area to improve the performance of ceramics in applications such as cutting tools, turbine parts and internal combustion engine parts.
Whiskers made of titanium nitride are of interest since the compound has a high melting point of 2950.degree. C., a hardness of 8-9 in Moh's scale, exhibits good electrical conductance and is stable at high temperatures in inert atmospheres. However, the processes for making TiN whiskers have required a gas phase reaction between TiCl.sub.4, N.sub.2 and H.sub.2 at temperatures above 1000.degree. C., with the attendant problems of controlling the gas flow rate and the disposal of the HCl by-product. These processes are not only very expensive due to the extreme conditions required, but they also result in low product yields. Therefore, there is a continuing need for improved processes for making transition metal nitride whiskers in general and titanium nitride whiskers in particular.